Cation-exchange product and process of making same



Patented Apr. 17, 1951 CATION-EXCHANGE PRODUCT AND PROCESS OF MAKINGSAME Frederick A. Hessel and Mcntclair, assignment search Corporation,sey, and one-half N. J assignors,

s, of one-h a corporation ofNew Jerto Ellis-Foster Company, a

William B. Canfield, by direct and mesne f to Montclair Recorporation ofNew Jersey No Drawing.

Application June 11, 1949,

Serial No. 98,645

v 12 Claims. 1

This invention relates to new and improved resinous base-exchangematerials. More particularly, it relates to the preparation of anactivated resin base-exchange material which is not only useful forpurifying and softening water but also for the removal of various otherdissolved substances from dilute aqueous solutions. The inventionrelates specifically to a new type of base-exchange material derivedfrom wallaba resin, and to a method of making it. The important aspectof the present process is the re movalv of calcium and/or magnesium ionsfrom .hard water.

The chief ingredient used in making the base exchange product is theresinous material of the wallaba tree Eperu'a falcata. The forests ofBritish Guiana contain large and fairly pure stands of wallaba trees.Wallaba wood is char acterized by the fact that it contains a reddishresinous substance present to the extent of about 25%. This resin isexceedingly complex in composition. It becomes insoluble and infusiblein the presence of aldehyde or aldehyde-containing substances and heat,a characteristic which may be indicative of the presence of phenolicbodies. It does not appear to be related to resin or other natural resinand does not dissolve when heated with drying oils such as linseed o'l.The resin is soluble in ethyl alcohol and acetone but insoluble inhydrocarbons. It is also very soluble in dilute aqueous sodium carbonateor sodium hydroxide solution.

The resin may be separated from the wood most easily by extraction withhot ethyl alcohol and it is'recovered from the solution by evapora tionof the solvent. It is a hard, brittle, dark red product, which initiallysoftens on heating but does not melt completely without decomposition.The resin may be separated from the wood also by repeated extractionwith dilute aqueous sodium carbonate or sodium hydroxide solution. Whenthe alkaline solution is neutralized with dilute acid a finely dividedresin precipitates which may be filtered off, washed, and dried.

The products of the present invention are made by treating wallaba resinor wallaba resin material with a concentrated inorganic acid, preferablyconcentrated sulfuric acid. The reaction may be carried out in variousways. Thus, concentrated sulfuric acid is allowed to react with (a)wallaba resin alone, (17) wallaba resin in the presence of an aldehydeor aldehyde-compound, or (c) a wallaba resin-aldehyde reaction product.When concentrated sulfuric acid is aldehyde.

- black brittle mass.

reacted with wallaba resin in the presence of an aldehyde or analdehyde-compound, the three ingredientsmay be mixed, or the aldehydemay be mixed with the acidprior to addition to the resin, or thealdehyde may be mixed with the resin prior to addition to the acid.Suitable. aldehydes and aldehyde-compounds are formaldehyde,paraforrnaldehyde, hexamethylenetetramine, furfural, acetaldehyde andthe like. The amount of aldehyde is. not critical but in any case it isless than 30% of the mixture of resin and Paraformaldehyde isadvantageously mixed with the concentrated acid. and wallaba resin addedto the mixture. On the other hand, furfural is best when mixed with theresin and the mixture added to the acid. When aqueous formaldehyde isused it is reacted with wallaba resin to form a wallaba resin-aldehydereaction product prior to the sulfuric acid treatment.

In practising the invention, one part of wallaba resin (or other wallabaresin material mentioned above) is treated with from 1 to 4 parts ofsulfuric acid of. specific gravity about 1.86 and allowed to react forfrom to 4 hours at -l2il C. The reaction between wallaba resin andconcentrated sulfuric acid is exothermic and the mass tends to heat up.However, the tempera ture is controlled so that the reaction mixture ismaintained at preferably 80-90 C. A certain amount of charring,dehydration, sulfonation and oxidation occurs to give a dark brown toThis is dumped into a large volume of water. lhe lumps are broken up andscreened to a desired size (for example, to pass through a 20-rneshscreen onto a 40-mesh screen) and finally washed until free of acid. Thewashed material is then allowed to stand. in contact with a dilute (e.g, 2%) aqueoussodium carbonate solution to remove any unreacted resin.After further washing with water to remove the alkali, the granules arepartially dried so that a given weight of material contains preferably50% to of water. Resins having cationexchange properties may also bemade in other more dilute acids. However, the exchange capacity of suchresins appears to be generally lower than that of resins prepared withconcentrated sulfuric acid.

The washed and partially died product may be employed as such or it maybe subjected to several cycles of exhaustion and subsequent regenerationwith dilute acid or concentrated sodium chloride brine solution. Thistreatment, however,- is not necessary since the materials of the presentinvention exhibit excellent ion-exchange 3 properties. Such propertiesdo not appear to be substantially changed by repeated exhaustion andregeneration.

The products of the present invention may be modified to alter theirion-exchange capacities in dium of alcohol or dilute aqueous sodiumcarbonate, whichever procedure is most fitting to the manufacturer.

The following examples are illustrative of the invention and are addedwith rapid stirring while maintaining the temperature at 80-90 C. Thereaction mixture heats up rapidly and becomes very dark. Ai-

ground to pass through a 20-mesh screen onto a IO-mesh screen. Theground material is then suspended in 2% aqueous sodium carbonate solution, washed, and partially dried. The screenings which pass through a20-mesh screen onto a 40- mesh screen are placed in a glass tube 1 inchin volume of water and washed. It is then ground to pass through a -meshscreen onto a IO-mesh ground material is then suspended A solution ofcalcium chloride containing 350.2 P. P. M.

parts of dry ion-exchange resin are employed, the

o bed possesses a capacity of 54.1 mgms. of calcium carbonate per gramof ion-exchange resin.

Example 3.Fifty parts of powdered wallaba concentrated sulfuric acid(specific grav1ty=l.86) are added with rapid stirring while maintainingthe tem- Derature at -90 C. The reaction mixture Water is passed throughfree of alkali and coloring matter. change material The ion-exis nowready for use.

change resin.

Example 4.Fifty parts of resin are placed in a GOO-ml. beaker immersedin formaldehyde in parts of concentrated sulfuric acid (specificgravity=1.86) is added with rapid stirring while maintaining the temperature at 80-90 C. The reaction mixture heated up rapidly and becomes intoa large volume of water and washed. It is then ground to pass through aZO-mesh screen The ground material is then suspended in 2% aqueoussodium carbonate, washed, and partially dried. The screenings which passthrough a 20-mesh screen onto a lo-mesh screen are placed in a tube 1inch in ution of calcium chloride containing P. M. of

of water are thus softened. dry ion-exchange resin are employed, the bedpossesses change resin.

A commercial synthetic cation-exchange resin (Amberlite IR was testedagainst the same 'is added with rapid stirring very dark.

calcium chloride solution in the same way. It

showed a capacity of 89.6 mgms. calcium carbonate per gram.

Example 5.--Fifty parts of powdered wallaba resin are placed in a600-ml. beaker which is immersed in a water bath. A mixture of parts ofparaformaldehyde in 240 parts of concentrated sulfuric acid (specificgravity=1.86)

While maintaining the temperature at 80-90 C. The reaction mixture heatsup rapidly and becomes very dark. After 4 hours at 80-90 C. into a largevolume of water and then washed, after which it is ground to passthrough a mesh screen onto a 40-mes'h screen. The ground material isthen suspended in 2% aqueous sodium carbonate, washed. and partiallydried. The screened resin is placed in a tube 1 inch in diameter to forma column 10 inches high. Distilled water is passed through the materialuntil the effluent is free of alkali and colored matter. Theion-exchangematerial is now ready for use.

A solution of calcium chloride containing 350.2

P. P. M. of hardness (calculated as calcium carbonate) is passed throughthe column. A total of 2700 ml. of water are thus softened. Since 11.0grams of dry ion-exchange resin are em= ployed, the bed, possesses acapacity of 85.9 mgms. of calcium carbonate per gram of ionexchangeresin. I

Example 6.Twenty-five parts of wallaba resin and parts of phenol areground together to form an intimate mixture and placed in a 600- ml.beaker.

A mixture of 10 parts of paraiormaldehyde in 200 parts of concentratedsulfuric acid (specific graVity=1.86) is added with rapid stirring whilemaintaining the temperature at 80-90 C. The reaction mixture heats uprapidly and becomes After 4 hours at 80-90 C. the batch is poured into alarge volume of water and then washed. It is then ground to pass througha 20- mesh screen onto a AO-mesh screen. The ground material is thensuspended in 2% aqueous sodium carbonate, washed and partially dried.The screenings which pass through a 20- mesh screen onto a 40-meshscreen are placed in a tube 1 inch in diameter to form a column 10inches high. Distilled water is passed through the column until theproduct is free of alkali and colored matter. The ion-exchange materialis now read for use.

A solution of calcium chloride containing 350.2 P. P. M. of hardness(calculated as calcium carbonate) is passed through the column. A totalof 2800 ml. of water are thus softened. Since 11.6 grams of dryion-exchange resin are employed, the bed possesses a capacity oft illmgms. of calcium carbonate per gram of ionexchange resin.

Example 7 .-Fifty parts of powdered wallaba resin are placed in aGOO-ml. beaker which is placed in a water bath. A mixture of 7.5 partsof paraformaldehyde and 192.5 parts of concen,

trated sulfuric acid (specific gravity=1.86) are added with rapidstirring while maintaining the temperature at 80-90 C. The reactionmixture heats up rapidly and becomes very dark. After 4 hours at thistemperature the batch is poured into a large volume of'water and washed.It is ground to pass through a 20-mesh screen onto a 40-mesh screen. Theground material is then suspended in 2% solution, washed, and partiallydried. The

aqueous sodium carbonate the batch is poured screenings which passthrough a 20-mesh screen onto a iO-mesh screen are placed in a glasstube 1 inch in diameter to form a column l0 inches high. Distilled wateris passed through the material until it is free of alkali and coloringmatter. The ion-exchange material is now ready for use.

A solution of magnesium sulphate containing 454.5 P. P. M. of hardness(calculated as magnesium carbonate) is passedthrough the column. Asecond columnof ion-exchange material from a commercial syntheticsulfonated resin known as Amberlite IR 100 was also treated with theabove hard water. Each ml. portion of effluent was examined as in theprevious examples, but in this case with a 5% 5 cc. sodium phosphatemade alkaline with concentrated ammonia. In each case after a breakthrough point was observed the columns were regenerated with 10% aqueousbrine solution and the cycle repeated. The bed capacities were thusdetermined as the number of mgms.

of magnesium carbonate absorbed by one gram of ion-exchange resin, andwere as follows:

Ambcrlite 1a 100 'E ram ple 8 Example 8.-Thirty parts of powderedwallaba resin and parts of ethanol are refluxed together at boiling toform a clear solution. Three parts of hexamethylenetetramine are nowadded and refluxing continued for 2 hours. sulting insoluble product isfiltered, powdered. The powdered material is 400-ml. beaker cooled bymeans of a water bath. One hundred twenty-five parts (ratio of 1 to 4)of concentrated sulfuric acid are added and the mixture agitated at -i10C. for 4 hours. The reaction mixture is then poured into a large volumeof Water, washed, After treatment with dilute aqueous sodium carbonatesolution and subsequent washing the material is now ready for use. A-column is prepared and treated with calcium chloride solution (350.2 P.P. M. calculated as calcium carbonate) as in. theprevious examples. 2500ml. of water are-thus softened. The material possesses a bed capacity of84.2 mgms. of calcium carbonate per gram of ion exchange material.

Eammple 9.Fifty parts of wallaba resin, 5 parts of sodium carbonate, andparts of water are warmed together to term a clear solution, the pH ofwhich is adjusted to '7.

dried and mixture refluxed at 80-90 minutes. A solid gel-like mass isformed which is broken up, dried and powdered. parts (.ratio of 1 to 4)of concentrated sulfuric acid are added and the mixture agitated at80'-90 C. for 4 hours. The reaction mixture is then poured into a largevolume of water, washed, ground, and screened. After treatment withdilute aqueous sodium carbonate and subsequent washing the material isnowready for use. A column is prepared and treated with calcium chloridesolution (350.2 P. P.1Vl. calculated as calcium carbonate) as in theprevious example. The material possesses a bed capacity of 7'? mgms. ofcalcium carbonate per gram of ion-exchange material.

reaction solution of The replaced in a ground, and screened.

Fifty parts oi 36 /2 aqueous formaldehyde are added and the ExampleZ0.Thirty parts of powdered wallaba resin and parts of ethanol arewarmed together under reflux to form a clear solution. Thirty parts of a36 70 aqueous solution of formaldehyde and 1 part of 7 acid solution areadded and the reaction mixture is heated to boiling under reflux. dishresinous mass precipitates from solution and thereafter refluxing iscontinued for 2 hours. The insoluble resinous material is filtered,suspended in 2% aqueous sodium carbonate solution, Washed free ofalkali, and screened. The screenings which pass through a ZO-mesh screenonto a -mesh screen are separated and placed in a glass tube 1 inch indiameter to form a column 10 inches high. Distilled Water is passedthrough the material until it is free of alkali and coloring matter.rial is now ready for use.

A solution of calcium chloride containing 350.2 P. P. M. of hardness(calculated as calcium carbonate) is passed through the column. Each ml.portion of effluent is tested with a 2 solution of ammonium oxalate todetermine at which stage cloudiness breakthrough of the hard Water.of-cloudiness, the column no longer is removing resin are employed, thematerial possesses a capacity of 27.5 mgms. of calcium carbonate pergram of ion-exchange material.

Example 11.Fifty parts of wallaba resin, 5 parts of sodium carbonate,and 95 parts of water are warmed together to form a clear solution. Thesolution is neutralized to a pH of 7 and a solution of 63.2 parts ofsodium bisulphite in 50 parts of 36%;% aqueous formaldehyde is added.

consisting of formaldehyde, paraformaldehyde, hexamethylenetetramine,furfural and acetaldehyde.

2. A cation-exchange resinous material comprising the reaction productof concentrated sulfuric acid and wallaba resin.

3. A cation-exchange resinous material comprising the reaction furicacid 7. The process of making a cation-exchange resinous material whichcomprises heating, for from to 4 hours at 120 C., l to 4 parts ofconcentrated sulfuric acid with one part of material selected from thegroup consisting of (a) wallaba resin, (b) a reaction product of wallabaresin and a resinous material which comprises heating, for to 4 hours at80-120 C., 1 to 4 parts of concentrated sulfuric acid with 1 part ofwallaba resin.

9. The process of making a cation-exchange resinous material whichcomprises heating, for to 4 hours at 80120 C., l to 4 parts acid with 1part of a formaldehyde, paraformaldehyde, hexamethylenetetramine,furfural and acetaldehyde.

he process of making a cation-exchange resinous material which comprisesheating, for to 4 hours at 80120 C., 1 to 4 parts of concentratedsulfuric acid with 1 part of a wallaba resin-formaldehyde reactionproduct.

11. The

12. The process of making a cation-exchange resinous material Whichcomprises heating, for from to 4 hours at 80-120 C., 1 to 4 parts ofconcentrated sulfuric acid with .1 part of a mixture of wallaba resinand paraformaldehyde FREDERICK A. HESSEL. WILLIAM B. CANF'IELD.

N 0 references cited.

1. A CATION-EXCHANGE RESINUOUS MATERIAL COMPRISING THE REACTION PRODUCTOF CONCENTRATED SULFURIC ACID AND MATERIAL SELECTED FROM THE GROUPCONSISTING OF (A) WALLABA RESIN, (B) A REACTION PRODUCT OF WALLABA RESINAND A COMPOUND SELECTED FROM THE GROUP CONSISTING OF FORMALDEHYDE,PARAFORMALDEHYDE, HEXAMETHYLENETETRAMINE, FURFURAL AND ACETALDEHYDE, AND(C) A MIXTURE OF WALLABA RESIN AND A COMPOUND SELECTED FROM THE GROUPCONSISTING OF FORMALDEHYDE, PARAFORMALDEHYDE, HEXAMETHYLENETETRAMINE,FURFURAL AND ACETALDEHYDE.